Firefox currently seems extremely fickle - with `pan-y` if fires pointercancel as soon as a touch strays even a pixel or so vertically.
While `touch-action: pan-y` would be ideal (allowing users to scroll the page even when their finger started the scroll on the carousel), this prevents a swipe that isn't perfectly/only horizontal to be recognised by Firefox.

in particular, no need to use originEvent, and preventDefault() only needed for touch events

these may also be the cause of weird behavior in Chrome/Surface, where scrolling vertically triggers slide advance

- my fault, my original advice of using `touch-action: pan-x` is exactly the value we *don't* want to have the browser handle...

Useful suggestion from Google in the Web App Manifest documentation.
https://developers.google.com/web/fundamentals/web-app-manifest/#start-url

In case we set `$body-bg` to a dark color, we have to keep table contrast relevant.

It seems it works without it.

This allows us to run `npm run dist` without tests.

Deleting external file since it is not needed, the copy of this file will be added directly to card.md.

Instead of using an external source since this is only a one time note it is safe to be placed within the document itself.

In the event that the content is larger than the image, the content will continue to be displayed outside the image itself. There are some workarounds but they apply only to browsers that support this option and IE11 is not one of them.

Also improve its formatting.

Broken after 787441d4.